processing results from INTERSECT, UNION or EXCEPT - Mailing list pgsql-novice

I'd like to do something as follows

SELECT t1.id FROM t1 WHERE t1.id IN (SELECT t2.id FROM t2 INTERSECT
SELECT t3.id FROM t3)

i.e. use results from a set-operation.
If i do this in psql, i get an error message

ERROR: parser: parse error at or near "intersect"

Is there any way to do this besides using a temporary table?

Thanx,
  Jody